Duffield, Lonnie
Current rating: 1474
Record: 7-9
| Grand Prix Phoenix 2020 (pioneer) | starting rating: 1506 | |||
| round | table | opponent (rating) | result | Δrating |
| 1pioneer | 67 | Jacob, Conor (1744) | Lost 0-2 | -141492 |
| 2pioneer | 297 | DeNatale, Nicholas (1514) | Lost 0-2 | -171475 |
| 3pioneer | 424 | Beam, Matthew (1498) | Won 2-1 | +181493 |
| 4pioneer | 330 | Hayes, Brook (1429) | Lost 1-2 | -191474 |
| top | average opponent: 1546record: 1-3 | new rating: 1474 | ||
| Grand Prix Las Vegas 2019 (modern) (modern) | starting rating: 1481 | |||
| round | table | opponent (rating) | result | Δrating |
| 1modern | 183 | Olofson, Sean (1510) | Lost 1-2 | -181463 |
| 2modern | 624 | Cooper, Tyler (1646) | Won 2-1 | +221485 |
| 3modern | 454 | Watson, Elizabeth (1455) | Won 2-1 | +171502 |
| 4modern | 537 | Heller, Blake (1630) | Won 2-1 | +201522 |
| 5modern | 304 | May, Trevor (1636) | Lost 1-2 | -151507 |
| 6modern | 262 | Whitten, Connor (1500) | Won 2-0 | +171524 |
| 7modern | 236 | Llewelyn, Stockton (1495) | Lost 1-2 | -181506 |
| top | average opponent: 1553record: 4-3 | new rating: 1506 | ||
| Grand Prix Dallas-Fort Worth 2019 (modern) | starting rating: 1500 | |||
| round | table | opponent (rating) | result | Δrating |
| 1modern | 146 | Huang, Erick (1500) | Lost 1-2 | -181482 |
| 2modern | 342 | Winsor, Garret (1436) | Won 2-0 | +171499 |
| 3modern | 55 | Blankenship, Chance (1480) | Lost 0-2 | -181481 |
| 4modern | 465 | Stedding, Michael (1481) | Won 2-0 | +181499 |
| 5modern | 349 | Alexander, Lucas (1502) | Lost 0-2 | -181481 |
| top | average opponent: 1480record: 2-3 | new rating: 1481 | ||